TUESDAY, July 25, 2017 (HealthDay News) -- It appears that $100 might go a long way toward convincing someone to get a colonoscopy.

New research found that such a cash incentive doubled the chances that older adults were screened for colon cancer.

"Colonoscopy is challenging for patients, requiring a day off from work, a bowel-cleansing preparation, and transportation, in addition to non-financial costs of anxiety and discomfort," said study author Dr. Shivan Mehta. He's an assistant professor of medicine at the University of Pennsylvania in Philadelphia.

"The improvement we saw in the rate of screening colonoscopies was statistically significant, and shows for the first time that a financial incentive can at least modestly boost that rate," Mehta added in a university news release.

Colon cancer kills more than 50,000 people in the United States every year, second only to lung cancer. But most potential tumors can be detected by colonoscopy and removed, usually before they become cancerous, researchers said.

The study included more than 2,000 people between the ages of 50 and 64. All were eligible for colonoscopy screening.

Some received an email asking them to opt in or opt out of a screening colonoscopy (the simple active choice group). Others received an email with the same message plus an offer of $100 if they had a colonoscopy within three months. A third group (the control group) received an email with just a phone number for scheduling a colonoscopy.

After three months, almost 4 percent of those in the $100 offer group had undergone a colonoscopy, compared with 1.6 percent in the control group and 1.5 percent in the simple active choice group.

The rate of colonoscopy appointment scheduling was 5 percent in the $100 offer group, 2.1 percent in the control group and 2 percent in the active choice group.

The effectiveness of the financial reward may be due to the large amount of money and the fact that it was offered along with easy access for booking an appointment, Mehta suggested.

"Although a $100 incentive seems relatively large, this amount is comparable to what employers already offer for completion of health risk assessments or biometric screening activities," he said.